Philadelphia Weekender: Bookstore Crawl and butterflies

🚢 Relive the '90s aboard the Olympia on the Delaware River on Friday.

• Wear your flannel and acid-wash jeans to the '90s-themed party running from 6-9pm. Tickets : $35

📚 The Philly Bookstore Crawl returns Saturday.

• Shops across the city and region are participating by offering special events, discounts and author signings.

🚲 Bike in your birthday suit! Philly's Naked Bike Ride is Saturday.

• The ride is about 12 miles and will kick off around 5pm. Starting location and route will be announced on the organizer's website on Friday.

🦋 Join fellow butterfly enthusiasts on Saturday for the annual count of the flying insects at the Discovery Center in Strawberry Mansion. 10am-noon

🎛 Elements of Hip Hop is hosting a community festival on Sunday from 11am-7pm at FDR Park in South Philly.

• Count on live performances, an art showcase, breakdancing battles and a DJ competition.

🇺🇦 The Ukrainian Folk Festival brings food, vendors and performances to the Ukrainian American Sport Center in Horsham on Sunday from noon-8pm. Tickets: $15 for those 15 years old and up.